Honing apparatus

ABSTRACT

A honing-stone assembly utilized in a honing head wherein the stone is forced outwardly into engagement with the workpiece. The novel construction residing in the use of a stone retainer having a portion deformable upon engagement with the workpiece to cooperate with the honing head and retain the stone therein as the stone is used and consumed.

Unite States Patent Kramm et al.

[ Feb. 15, 1972 [54] HONING APPARATUS [72] Inventors: Carl H. Kramm, Pinckney; Roger E. Lee,

Brighton, both of Mich.

[73] Assignee: Wedge-Lock Honing Stone Co., Brighton,

Mich.

[22] Filed: July 13, 1970 21 Appl. No.: 54,403

[52] U.S. Cl ..5l/204, 51/346 [5 l] Int. Cl. ..B24b 5/10, B24d 17/00 [58] Field of Search ..5 H204, 33l, 338-340,

[56] References Cited UNITED STATES PATENTS 2,952,952 9/1960 Stanhope ..5l/204 2,991,597 7/196l Calvert ..5 H204 3,037,333 6/ 1962 Stelmachowski ..5 l /204 X 3,195,280 7/1965 Crowe ..5l/204 Primary Examiner-Donald G. Kelly Attorney-Beaman & Beaman [57] ABSTRACT A honing-stone assembly utilized in a honing head wherein the stone is forced outwardly into engagement with the workpiece. The novel construction residing in the use of a stone retainer having a portion defonnable upon engagement with the workpiece to cooperate with the honing head and retain the stone therein as the stone is used and consumed.

l 1 Claims, 6 Drawing Figures PATENTEDFEB 15 I972 3.641.! 1 5 3! FIG 2 M /2 M 2/ 1 (A I o7 36 F154 INVENTOR CARL H. KRAMM 4 58 ii ROGER E. LEE

ATTORNEYS HONING APPARATUS BACKGROUND OF THE INVENTION The invention pertains to the field of honing devices wherein a plurality of honing stones are mounted within a head, and are radially adjustable by means of an internal member within the head adapted to outwardly displace the stones.

A common hone construction utilized to finish the bores of workpieces with an accurate and smooth surface includes a hone head having a plurality of radially disposed openings defined therein for receiving abrasive elements. Internally, the hone includes an axially movable stone-adjusting member, usually in the form of a wedge, which engages the inner surface of the stones or the stones support, to adjust the stone body radially outwardly as it is consumed, and in order to produce the desired honing pressure.

While this type of hone is effective with respect to its metalfinishing capabilities, problems have been encountered in retaining the abrasive stone body within the hone head openings, particularly as the stone wears. Thus, upon removal ofthe hone head from the workpiece bore, it is not uncommon for a hone stone to drop or fall from its opening, thereby necessitating attention by the operator, which is time consuming and expensive. This common fault of honing apparatus has attempted to be overcome by utilizing various devices for retaining the honing element within its head. Reference is made to U.S. Pat. Nos. 3,037,333; 3,264,789 and 3,403,481, which show honing stone devices in conjunction with retainers attempting to overcome the aforedescribed problem. Unfortunately, the prior work done in seeking to overcome the problem of retaining the hone stone elements in position has not adequately solved the problem, and the instant invention is directed to an improved hone stone body retainer.

The retainers of the aforedescribed patents have the limitation of being expensive, and are not positive in their operation. Furthermore, the majority of honing heads now in use are of the type shown in U.S. Pat. Nos. 3,037,333 and 3,403,481 wherein the openings within the hone head are of an oblong configuration, and the abrasive stone retainer is of a similar shape while the stone itself is rectangular. This construction results in the actual abrasive element being of significantly less length than the opening within the honing head, reducing the ability of the hone to remove metal as compared with the length ofthe hone head opening.

SUMMARY OF THE INVENTION It is an object of the invention to provide a hone stone assembly, including a retainer, which is of an economical construction, capable of maximum metal removal and finishing within a given size hone head opening, and capable of forming a positive retaining relationship with its hone head to prevent accidental removal or disassembly therefrom.

The hone assembly in accord with the invention utilizes an abrasive stone body having inner and outer surfaces obliquely related to each other, whereby the angular deviation between the surfaces corresponds to the wedge angle of the hone head actuator. A metallic retainer ofa U-shaped configuration is affixed to the stone body and includes a base portion which is preferably bonded to the inner surface of the stone. The retainer also includes leg portions which depend from the base portion and are disposed adjacent the stone body ends.

One of the retainer leg portions is of an undeformed length greater than the distance between the stone body inner and outer surfaces adjacent the associated body end wherein the free end of the leg portion extends radially outwardly beyond the body outer surface. Upon the hone stone assembly being located within the honing head, and as the honing head is inserted into the workpiece bore, the outwardly projecting end of the one leg portion engages the workpiece and is thereby radially forced inwardly which causes a deformation of the retainer leg portion bowing the leg portion outwardly with respect to the associated stone end. This bowing" or deformation of the leg portion causes the deformation to underlie that portion of the hone head adjacent an end of the opening in which the stone assembly is received producing a positive locking or retaining of the hone stone assembly in its opening.

As the stone wears, the actuator of the honing head is axi ally displaced to force the hone stones outwardly. The deformed portion of the retainer is such as to permit radial movement of the stone outwardly, yet maintain the positive retaining relationship with the head.

Deformation of the retainer leg portion is facilitated by deformation aiding means in the form of a plurality of spaced notches formed on the leg portion. Preferably, these notches are defined on the side of the leg portion disposed toward the stone, and aid deformation by producing localized reduced cross-sectional areas in the leg portion.

Additionally, the association between the retainer and the honing head is aided by the presence of oblique surfaces defined upon the hone head at the opening end adjacent the deformable leg portion of the retainer, and a corresponding oblique surface is defined on the deformable leg portion.

DESCRIPTION OF THE DRAWINGS The aforementioned objects and advantages of the invention will be appreciated from the following description and accompanying drawings wherein:

FIG. 1 illustrates a hone head utilizing hone stone assemblies in accord with the invention prior to insertion of the head into the workpiece, and prior to deformation occurring within the hone stone retainer,

FIG. 2 is an enlarged detail, elevational, sectional view of a hone stone assembly just prior to being received in the workpiece bore,

FIG. 3 is an enlarged detail, elevational, sectional view similar to FIG. 2 illustrating the relationship of the components upon the hone head being inserted in the workpiece, and deformation occuring within the hone stone retainer,

FIG. 4- illustrates the relationship of the hone stone assembly components after use of the hone, and after wear on the stone has occurred,

FIG. 5 is a perspective view of the hone stone retainer, per se, in accord with the invention, and

FIG. 6 is an elevational view of an assembled hone stone and retainer prior to insertion into a hone head.

DESCRIPTION OF THE PREFERRED EMBODIMENT The basic relationship of the components of a honing head utilizing the hone stone assembly of the invention will be appreciated from FIG. 1. The honing head 10 is of an elongated, hollow, configuration having an outer cylindrical surface of a diameter slightly less than the diameter of the workpiece bore 12 which is to be honed whereby the head may be received within the workpiece 14.

A plurality of hone stone receiving openings 16 are defined in the head 10 circumferentially spaced about the hone, 3, 4 or 5 openings being usually employed. In the disclosed embodiment, one of the features of the invention lies in the rectangular configuration of the hone stone assembly, and the openings 16 are of a rectangular configuration to correspond to the hone stone assembly.

As will be appreciated from FIGS. 2 through 4, the hone head 10 includes a surface 18 which defines a portion of the stone-receiving openings 16 and which is slightly obliquely re lated to the vertical in the order of 4. Also, an oblique surface 20 is defined on the hone head adjacent openings 16 and intersects the surface 18, and is disposed at 45 to the horizontal.

Radial adjustment of the hone stone assembly is accomplished through the tapered actuator 22 which is axially shiftable within the hone assembly by adjusting mechanism, not shown, and the actuator includes a tapered surface 24 of a planar configuration disposed in alignment with each opening. The basic relationship of the honing head 10 and the actuator 22 is well known in the hone art and forms no part of the instant invention.

The hone stone 26 in accord with the invention is of a generally rectangular configuration including an outer surface 28, an inner surface 30, ends 32 and 34, and lateral sides. The inner surface 30 is obliquely related to the outer surface 28 at an angle corresponding to the angle of the actuator surface 24 whereby a corresponding compensating relationship exists to ensure that the hone outer surface 28 is parallel with the axis of the hone head 10. As will be appreciated from FIG. 1, the hone stone ends 32 and 34 are substantially perpendicularly disposed to the length of the hone stone.

The hone stone 26 is retained within its associated opening 16 by means of a metallic retainer having a configuration which will be best appreciated from FIG. 5. The retainer 36 may be formed of a relatively soft, deformable metal such as copper, bronze, aluminum or the like, and is ofa longitudinal configuration having a base portion 38 from which leg portions 40 and 42 depend. The width of the retainer 36 substantially corresponds to the width of the stone body 26, and the distance between the inner surfaces of the leg portions 40 and 42 corresponds to the length of the stone 26 when the assembly is placed in an opening 16 whereby the stone may be closely received within the retainer as will be apparent from FIGS. 1 and 2. The leg portions 40 and 42 are initially inclined outwardly away from the stone body 26 to provide a biasing force that aids in maintaining the stone assembly in the openings 16.

The leg portion 40 is of a greater length than the portion 42 for two reasons. One reason for the greater length is that the distance between the surfaces 28 and 30 adjacent the: end 32 is greater than at the end 34. Additionally, it is desired that the free end 44 of the leg portion 40 extend outwardly beyond the hone outer surface 28 as will be appreciated in FIG. 2, while the end of the leg portion 42 will be substantially aligned with the hone outer surface 28. In order to aid in the deformation of the leg portion 40, a plurality of notches 46 ofa V cross section are defined in the leg portion, FIG. 5, which produce reduced cross-sectional thicknesses in the leg portion which extend transverse to the length of the leg portion and aid in the outward deformation of the leg portion, as will be later apparent. in addition to the notches 46, the leg portion 40 includes an obliquely disposed surface 48 defined thereon for cooperation with the hone head surface 18. The surface 48 and the notches 46 may be stamped into the leg portion 40 due to the softness and ductile nature of the retainer material.

The retainer 36 is assembled to the stone 26 by placing the stone within the retainer as will be apparent from the drawings. The leg portions 40 and 42 will be disposed as shown in HO. 6 and the base portion 38 will be located adjacent the stone inner surface 30. An adhesive is interposed between the base portion and the stone inner surface to firmly affix the base portion to the stone and thereby assure the relationship between the stone and retainer.

The assembled stone and retainer are then placed in a bone head opening 16, and the actuator 22 is so positioned that the stone assembly may be substantially fully received within the opening as will be apparent in FIG. 2.

The workpiece 14 includes a beveled entrance surface 50 which is concentric to and intersects the workpiece bore 12, and relative axial movement between the workpiece and honing head causes the surface 50 to engage the free end 44 of the leg portion 40. This engagement between the surface 50 and the leg portion 40 produces a radially inward compression force on the leg portion causing the leg portion to deform in the manner illustrated in FIG. 3. The presence of the notches 46 aids in this deformation, which is away from the stone body 26 to produce a bowing of the notched portion of the leg portion.

As the leg portion 40 is forced inwardly by the surface 50 the leg portion surface 48 will cooperate with the honing head surface 18, which is of a corresponding angle, and produce a close fit between the leg portion 42 and the honing stone end 34 and hone head surface 52 preventing longitudinal shifting of the stone, and the confinement of the leg portion 40 adjacent its free end by the cooperation of the surfaces 18 and 48 assures that the bowing" will occur as indicated. The deformation in the leg portion 40 forms a permanent set in the leg portion, and as the bowed" portion of the leg portion is now disposed below" the head surface 20, a positive locking arrangement of the hone assembly within its associated opening 16 occurs. Additionally, the presence of the cooperating surfaces 18 and 48, and the tendency for the leg portion 40 to somewhat function as a spring to bias the hone assembly to the right, FIG. 3, causes a constant frictional engagement between the leg portion 42 and the head opening surface 52 which resists outward unintentional movement of this end of the hone assembly with respect to the head.

As the leg portions 40 and 42 initially extend away from the body 26, FIG. 6, the leg portions firmly engage the surfaces 18 and 52 upon the assembly being inserted into the opening 16 and thus hold the hone stone assembly in its associated opening until the leg 40 is bowed," as described above.

FIG. 3 illustrates the relationship of the components once the head 10 is completely inserted within the workpiece bore, and relative rotation is produced between the workpiece and head to create the honing action. As the honing action continues, the actuator 22 is moved or biased to the right to maintain engagement between the hone stone outer surface 28 and the bore 12 to permit the removal of metal. As the workpiece metal is removed, the free ends of the leg portions 40 and 42, which are in engagement with the workpiece, will also be worn, but as the leg portions are formed of a soft material, no adverse effect on the workpiece occurs.

FIG. 4 illustrates the relationship of the hone stone assembly and head upon removal of the head 10 from the workpiece bore after the hone assembly has been used and slight wear in the stone has occurred. ln this relationship, it will be noted that the natural resiliency of the metal of the leg portion 40 will cause the free end 44 to slightly extend beyond the hone outer surface 28 for depression once the head is again inserted into a workpiece bore.

As the hone assembly is moved outwardly by the actuator 22 as the hone stone assemblies wear, the degree of bowing" of the deformed portion of the leg portion 40 increases as the leg 40 will not wear as quickly as the stone 26, and the interlocking of the retainer and the head actually increases as the stone wears.

After sufficient wear on the hone stone assembly has occurred, the assemblies may be removed from their associated openings 16 by translating the actuator 22 in the direction which radially moves the hone stones and retainers outwardly, and the operator by gripping the bone assemblies adjacent the leg portion 42 may, by hand or by using known tools, pivot" the hone stone assemblies from their opening 16 by raising the leg 42 and end 34 first which pivots the deformed portion of the leg portion 40 away from the surface 20 permitting ready removal of the hone assembly from its opening.

The rectangular configuration of the hone stone assemblies permit a maximum amount of abrasive material to engage the workpiece bore with respect to the dimension of the opening 16 defined in the head 10, and it has been found that the required honing time, and the life of the hone stones, can be significantly improved by the use of the rectangular stone configuration. Hone stone assemblies employing the concepts of the invention have been found to completely eliminate the heretofore commonly experienced problem of the hone as semblies inadvertently falling from or dropping out of the associated hone head opening, or conversely, being so tight as to distort the hone body due to pressure on the sides of the openings 16, and yet the retainer 36 is of a very economical construction and readily producible by high-production manufacturing techniques.

lt is appreciated that various modifications to the inventive concept may be apparent to those skilled in the art without de parting from the spirit of the invention.

We claim:

1. A hone stone assembly for use with honing heads having rectangular stone-receiving openings and an internal stone support and expander comprising, in combination, an abrasive stone body of an elongated configuration having first and second ends, lateral sides, an outer surface and an inner surface, a retainer element attached to said body, a deformable portion defined on said element extending from adjacent said body inner surface to adjacent said outer surface, said deformable portion including an outer end initially extending beyond said body outer surface whereby compression of said deformable portion by force applied to said outer end deforms said deformable portion away from said stone body to form a retaining relationship with the honing head.

2. In a hone stone assembly as in claim 1 wherein said retainer element includes a base portion and stone-embracing leg portions depending from said base portion, one of said leg portions constituting said deformable portion, and bonding means bonding said base portion to said stone body inner surface.

3. In a hone stone assembly as in claim 2 wherein said stoneembracing leg portions are disposed adjacent said stone body ends and said ends are substantially perpendicular to the length of said body.

4. In a hone stone assembly as in claim 1 wherein said retainer is formed of metal and said deformable portion includes deformation-aiding means to control the location of deformation occurring in said deformable portion.

5. In a hone stone assembly as in claim 1 wherein said retainer is formed of metal and is of a substantially U-shaped configuration including a base portion and leg portions depending from said base portion, said leg portions being disposed adjacent said body ends, bonding means bonding said body inner surface to said retainer base portion, said deformable portion comprising one of said leg portions.

6. In a hone stone assembly as in claim 5 wherein deformation aiding means are defined in said leg portion constituting said deformable portion.

7. In a hone stone assembly as in claim 6 wherein said one leg portion is of undeformed length greater than the distance between said inner and outer body surfaces at said body end adjacent said one leg portion whereby the free end of said one leg portion extends beyond said outer surface.

8. In a hone stone assembly as in claim 7 wherein said deformation aiding means comprises elongated notches defined in said one leg portion reducing the transverse cross-sectional area of said one leg portion at predetermined locations.

9. A hone stone assembly comprising, in combination, an elongated abrasive stone body having ends, lateral sides and inner and outer surfaces, a stone body retainer mounted upon said body, said retainer including a base portion affixed to said body and leg portions depending from said base portion and disposed adjacent each stone body end, at least one of said leg portions being deformable to bow away from the associated body end and extending beyond said body outer surface in the undeformed state.

10. In a hone stone assembly as in claim 9 wherein deformation aiding means are defined on said one leg portion to facilitate bowing of said one leg portion.

11. In a hone stone assembly as in claim 10 wherein said deformation-aiding means comprises a plurality of notches defined in said one leg portion each having a length extending transversely to the length of the associated one leg portion. 

1. A hone stone assembly for use with honing heads having rectangular stone-receiving openings and an internal stone support and expander comprising, in combination, an abrasive stone body of an elongated configuration having first and second ends, lateral sides, an outer surface and an inner surface, a retainer element attached to said body, a deformable portion defined on said element extending from adjacent said body inner surface to adjacent said outer surface, said deformable portion including an outer end initially extending beyond said body outer surface whereby compression of said deformable portion by force applied to said outer end deforms said deformable portion away from said stone body to form a retaining relationship with the honing head.
 2. In a hone stone assembly as in claim 1 wherein said retainer element includes a base portion and stone-embracing leg portions depending from said base portion, one of said leg portions constituting said deformable portion, and bonding means bonding said base portion to said stone body inner surface.
 3. In a hone stone assembly as in claim 2 wherein said stone-embracing leg portions are disposed adjacent said stone body ends and said ends are substantially perpendicular to the length of said body.
 4. In a hone stone assembly as in claim 1 wherein said retainer is formed of metal and said deformable portion includes deformation-aiding means to control the location of deformation occurring in said deformable portion.
 5. In a hone stone assembly as in claim 1 wherein said retainer is formed of metal and is of a substantially U-shaped configuration including a base portion and leg portions depending from said base portion, said leg portions being disposed adjacent said body ends, bonding means bonding said body inner surface to said retainer base portion, said deformable portion comprising one of said leg portions.
 6. In a hone stone assembly as in claim 5 wherein deformation aiding means are defined in said leg portion constituting said deformable portion.
 7. In a hone stone assembly as in claim 6 wherein said one leg portion is of undeformed length greater than the distance between said inner and outer body surfaces at said body end adjacent said one leg portion whereby the free end of said one leg portion extends beyond said outer surface.
 8. In a hone stone assembly as in claim 7 wherein said deformation aiding means comprises elongated notches defined in said one leg portion reducing the transverse cross-sectional area of said one leg portion at predetermined locations.
 9. A hone stone assembly comprisiNg, in combination, an elongated abrasive stone body having ends, lateral sides and inner and outer surfaces, a stone body retainer mounted upon said body, said retainer including a base portion affixed to said body and leg portions depending from said base portion and disposed adjacent each stone body end, at least one of said leg portions being deformable to bow away from the associated body end and extending beyond said body outer surface in the undeformed state.
 10. In a hone stone assembly as in claim 9 wherein deformation aiding means are defined on said one leg portion to facilitate bowing of said one leg portion.
 11. In a hone stone assembly as in claim 10 wherein said deformation-aiding means comprises a plurality of notches defined in said one leg portion each having a length extending transversely to the length of the associated one leg portion. 